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Which clause is not applicable in views?
ORDER BY clause
The SELECT statement which is used to create the view should not include GROUP BY clause or ORDER BY clause. The SELECT statement should not have the DISTINCT keyword. The View should have all NOT NULL values. The view should not be created using nested queries or complex queries.
What is the difference between view and SELECT statement?
Once the view is created, your application developers will have to deal with the SELECT statements using column in the same view, hence the term virtual table. Security: or just called it access control. Most relational database management system allow properties in the view object that control the type of access.
What is a view Why should you use a view?
Views can act as aggregated tables, where the database engine aggregates data (sum, average, etc.) and presents the calculated results as part of the data. Views can hide the complexity of data. For example, a view could appear as Sales2000 or Sales2001, transparently partitioning the actual underlying table.
Can we create indexes on views?
Indexes can only be created on views which have the same owner as the referenced table or tables. This is also called an intact ownership-chain between the view and the table(s). Typically, when table and view reside within the same schema, the same schema-owner applies to all objects within the schema.
Do database views take up space?
For this reason, the view does not take up any disk space for data storage, and it does not create any redundant copies of data that is already stored in the tables that it references (which are sometimes called the base tables of the view).
What is the difference between view and query?
Views are a special version of tables in SQL. The view is a query stored in the data dictionary, on which the user can query just like they do on tables. It does not use the physical memory, only the query is stored in the data dictionary. It is computed dynamically, whenever the user performs any query on it.
Which of the following is an advantage of a view?
A view can draw data from several different tables and present it as a single table, turning multi-table queries into single-table queries against the view.
Is there a reason to not use select in a view?
Yes, there are reasons to not use SELECT * in a view. The most important is that SQL Server caches the metadata of a view’s output, and it doesn’t magically update if underlying objects change.
Where can I find the definition of a view?
You can gain information about a view’s definition or properties in SQL Server by using SQL Server Management Studio or Transact-SQL. You may need to see the definition of the view to understand how its data is derived from the source tables or to see the data defined by the view.
What is the definition of a view in SQL?
In other words, you can use this view to return information about objects of various types, including functions, stored procedures, and of course, views. One of the columns returned with this view is called definition.
Can a user see the object definition in SQL Server?
A select against the OBJECT_DEFINITION function will return a value of NULL if the user does not have permissions to see the meta data. By default users were able to see object definitions in SQL Server 2000, but in SQL Server 2005 this functionality was removed to allow another layer of security.